Surgical cast



Patented Nov. 20, 1951 EFICE SURGICAL CAST John E. Means, Seattle, Wash.

N 0 Drawing. Application July 16, 1946, Serial No. 684,001

1 Claim.

This invention relates to improvements in means and methods forpreparing casts for the support of anatomical segments, particularlycasts for supporting broken bones in the human body or in the body of ananimal.

Heretofore it has been a slow and difficult procedure to place a rigidcast on the body of a living person or animal to support and align abroken bone while it is knitting. This problem is especially difiicultwith domestic animals and in many instances valuable animals have beenkilled because it was considered impossible or impractical to try toplace a cast on a broken leg to assist nature in knitting the fracture.

Furthermore such surgical casts have been uncomfortable to the wearerbecause they have been big and heavy and have not always fittedcorrectly, often causing serious irritation. Another difficulty has beenthat casts of the usual type are more or less air tight, thus excludingair from the part of the body so encased to the detriment thereof andmaking inspection difficult.

Therefore it is an object of the present invention to provide the meansand method of making a surgical cast on a living body that overcomes, toa large extent, the shortcomings and difiiculties above set forth. Theimproved cast or support can easily and quickly be placed on the bodywhere desired, it will fit well, it is practice of cutting a window inthe cast for inspection and so the doctor or nurse can smell the encasedmember to determine conditions within.

In order to accomplish these improved results, cloth such as surgicalgauze or the like, is impregnated with a chemical that has the power toact as a catalyst with reference to a solution, such as a solution of asynthetic resin, to cause polymerization within said solution whenapplied to the gauze, thus to form a rigid solid conformingsubstantially to the size and shape of the gauze.

Gauze so prepared and impregnated can be wrapped or otherwise placedabout an anatomical segment in a living body, human or animal, while thegauze is soft pliable. in this condition the gauze is easy and light tohandle and its placement on the anatomical segment can be accomplishedquickly with a minimum of effort by the attendant and a minimum ofdiscomfort to the patient.

Immediately after the treated gauze: is thus placed about the part ofthe body to be sup ported, the solution is painted, with a suitablebrush, onto the gauze, whereupon polymerization begins, and shortly athin, stiff, strong and rigid solid body is formed corresponding to theposition and shape of the gauze around the anatomical part to besupported.

While many different chemicals can be used to impregnate the gauzeaccording to this inventive concept, some of the preferred chemicalsare: a non-aqueous solution of a weak organic acid such as citric acidor oxalic acid: or ammonium salts of stronger acids, for instance,ammonium sulphate or ammonium chloride: or the salt of a very weak baseand a strong acid such as urea nitrate or hydroxylamine hydrochloride.

A preferred solution for treating and impregnating the gauze to depositthereon a catalyzing agent that will cause polymerization in a solutionof synthetic resin such as a urea-formal dehyde aqueous syrup follows:

Urea nitrate 3.0 to 4.0 grams Urea 12 grams Methyl cellulose 6 gramsAlcohol (denatured ethyl) 300 cc.

This mixture is used at a temperature just below its boiling point andthe gauze is drawn through it and immediately dried and placed withinwater-proof coverings where it will keep indefinitely as an article ofcommerce.

After the gauze so treated and impregnated is in place to form a castabout a bodily segment, the solution of resin or the like, is paintedthereon and the time required for solidification of the resin willdepend partly on the strength of the acid in the chemical on the gauze.Normally setting of the cast will begin in a few minutes and it willbecome quite stiff within less than half an hour. Thus is formed a castfor the support of a broken bone or the like, in a living body, that islight in weight and stronger than plaster. It is more comfortable to thepatient and fits the part well. It will have many minute ventilatingpores because the gauze is woven with an open mesh. It is water proof.

The solution of synthetic resin employed may be any of the articles ofcommerce now on the market. The formulas of these resin solutions, perse, are not a part of this invention. The

" invention resides in the article of manufacture 7 3 that is thetreated and impregnated gauze and the methods of procedure herein setforth.

I claim:

The method of making a cast for the support of an anatomical segment ofa living body, that comprises impregnating a bandage with a chemicalthat has the property of a potential catalyizing agent with reference toa solution of resin, wrapping the anatomical segment with said bandage,and then applying a solution of resin to the bandage in place on thesegment whereby said resin solution is polymerized to form a 4 rigidsolid substantially conforming to the size, shape and position of thebandage.

JOHN E. MEANS.

REFERENCES CITED The following references are of record in the file ofthis patent:

,UNITED STATES PATENTS.

